1. Field of the Invention
The present invention relates to a computer program product, system, and method for replication of data objects from a source server to a target server.
2. Description of the Related Art
Data replication is used to replicate data belonging to multiple nodes from one server to another server, so that if the main source server to which data is being backed-up goes down, the clients can recover their data from the replication site. A storage-management server such as Tivoli® Storage Manager (TSM) stores data objects in one or more storage pools and uses a database for tracking metadata about the stored objects. (Tivoli is a trademark of International Business Machines Corporation worldwide). The storage management server may replicate the data objects to a remote location for disaster recovery purposes. Some of the methods used to transfer data to a remote location include physically transporting tapes containing copies of the data from the source site to the disaster recovery site, electronically transmitting the data (TSM export/import) or using hardware replication of the source site disk storage to create a mirror of the data. Available replication hardware devices include Virtual Tape Library (VTL) products that perform block-level replication using deduplication hardware.
Data deduplication is a data compression technique for eliminating redundant data to improve storage utilization. Deduplication reduces the required storage capacity because only one copy of a unique data unit, also known as a chunk or extent, is stored. Disk based storage systems, such as a storage management server and Virtual Tape Library (VTL), may implement deduplication technology to detect redundant data chunks, and reduce duplication by avoiding redundant storage of such chunks.
A deduplication system operates by dividing a file into a series of chunks, or extents. The deduplication system determines whether any of the chunks are already stored, and then proceeds to only store those non-redundant chunks. Redundancy may be checked with chunks in the file being stored or chunks already stored in the system.
There is a need in the art for improved techniques for replicating objects from one server to another.